My hunting partner shoots with a PSE bow his draw length is 30" set at 70 pounds. He is using 125 gr broad heads.

I am using the Mathews FX set at 70 pounds draw at 28" and broad head weight 100gr. The Mathews bow consistently penetrates the butt approximately 200mm deeper than the PSE.

My question is why? Is the PSE slower than the Mathews, could it be the set up of the bow? Surely the difference shouldn't be so great?

How do you check if your penetration is sufficient for Wildebeest / Kudu sized game?

Thank you

You've got to answer more questions first... How many blades does each head have? 2,3,4...? And cutting diameter of the heads? Blade thickness? Arrow weight? All of these factors play a vital role in determining penetration. For instance, if your partner is shooting 125gr heads with 4 blades and 1.25" cutting diameter, on top of a light arrow, then penetration won't be as good as if you're shooting a small diameter 2 or 3 blade head on a heavier arrow. Alot of people here will give you the generic "heavier arrow penetrates better", but that's not always the case. There are many more factors than just arrow weight that determine penetration.

Mancannon hit it on the head.

Arrow weight, dia of the shaft, sharpness of the blades, speed of the arrow, etc. all play a role in penetration.

Good Luck

Reloader

ghundwan,

It gets even deeper than what Man said. Every bow out there has and "effieceny" rating. Its based on how much energy is transfered to the arrow and how much is lost through noise, vibration, etc. Some bows are much more effiecent than others therby having better penetration. The most effiecent bow as tested by Norb Mullany is the Oneida.(yes Im biased)

Secondly, a bow is more effiecent the closer you are to its top weight range. So a 60-70lb bow shot at 62lbs would be less effiecent than a 50-60lb bow shot at 58lbs. That means the 58lb bow MAY penetrate better.

Also, if a bow isn't precisely tuned the arrows could be flying untrue. This means they are hitting the target on an angle rather than head on, this would change the penetration over a well tuned bow and arrow.

Let off also weighs in, if your shooting a bow with 65% let off and hes shooting one with 80%, his bow will be slower and penetrate less.

Lastly, depending on where your draw length is in "valley" of the let off will have a direct affect on speed and effieceny. Shooting a bow deep in the valley will slow a bow down (your using all the letoff available)versus shooting the bow right at the cam roll over(probably not reaching the full let off).

So it could be anyone or a combination of those things....

Hugh

I have owned a lot of PSE bows and on the average, they are very slow as are the Golden Eagle bows. Most were only a little faster then a recurve. Even though the arrow was heavier, to get penetration, the heavy arrow still has to go fast. If his arrow was going the same velocity as yours, then you would see a difference. There are a lot of factors involved, shaft diameter, number of blades, shaft stiffness, bow tuning, bow efficiency, and many other things.
The best penetration is a heavy arrow going as fast as it can be driven without being out of tune. A light fast arrow can penetrate but it can be stopped or deflected very quickly if an obstuction is encountered.
Then there are the stories of the arrow going so fast that a broadhead will not shoot. The simple answer is that the bow weight and efficiency has gone beyond the spine of the arrow and it can not be tuned. So the mechanical head is chosen only to find that the lack of momentum of the light arrow causes a loss of penetration.
There is no way around physics or we would run our cars on water.
What would you rather be hit on the head with, an apple falling from a tree or a lead ball?

Thank-you for the insight, even when using field points of the same weight as the broad heads i.e. 100 (Mathews) and 125 gr (PSE) the penetration difference is also approximately 200mm. My arrows are slightly thinner than his, not sure how much though.

I would really appreciate your thoughts as to wither the PSE has enough penetration to effectively put down a Kudu Bull assuming its shot in the vitals? My partner has lost confidence in the bow?

Ghundwan, can you give more specifics about the PSE bow? Which model is it? It should say on the limbs. For a Kudu bull, you're going to need a fair amount of kinetic energy. Most of the PSE's will deliver what you're looking for, unless it's really old. You're best bet is to use a robust, cut on contact broadhead, preferably a two blade configuration.

As a side note, it's impossible to determine penetration by brand name. PSE makes some serious bows, Mathews does too. I own one of each. The PSE is just barely less powerful than the Mathews. The Mathews is just much much smoother. Both will take a Kudu bull, but only with the proper arrow and broadhead. Good luck!!

ManCannon

The PSE is a Nova single cam and the Mathews FX single cam.

We are obviously both novices to Bow hunting and your help and info is greatly appreciated

quote:

The best penetration is a heavy arrow going as fast as it can be driven without being out of tune. A light fast arrow can penetrate but it can be stopped or deflected very quickly if an obstuction is encountered.

This only applies to bows with very slow speeds, i.e. old compounds and recurves. Modern bows with IBO speeds close to 300+ fps will not suffer from the light versus heavy arrow as much as you'd think. Penetration is not due to momentum or kinetic energy. They're properties of a moving arrow, but that's not the mechanism of penetration. The mechanism behind penetration is force, and it can be calculated using Newton's "F=MA", where A is now deceleration, and mass is the arrow weight. I've run hundreds of scenarios now that simulate soft and hard impacts. For instance, if a 350gr arrow and a 700gr arrow are launched from the same bow, (350gr = 315fps / 700gr = 210 fps), and a soft object is encountered, i.e. the arrow comes to rest after penetrating 20 inches, the 350gr arrow exerts 205 pounds of force while the 700gr arrow exerts 183 pounds of force. An arrow weighing 470gr will exert the maximum amount of force for this particular scenario, delivering 216 pounds. What happens when it hits a hard object? Suppose the arrows have to stop in 1.0", i.e., a heavy bone. The 350gr arrow is now exerting 925 lbs of force, the 700gr arrow is exerting 822 lbs of force, while the 470gr arrow is exerting 975 lbs of force. Will the bone break??? That's where projected frontal area of the broadhead comes into play. The fewer the blades, the less the frontal area is, thus ultimately increasing pressure exerted on the bone... If for instance, your broadhead has a projected frontal area of 0.085 square inches, you can now calculate pounds per square inch. Back to the hard impact example, the 350gr arrow is now applying 10,882 psi to the bone, the 700gr arrow is applying 9670 psi, while the 470gr arrow is applying 11,470 psi to the bone. Hopefully the bone you just hit will break well under this pressure so that your arrow can now continue it's penetration. Momentum and KE are generic guidelines to gauge possible performance, but it really boils down to impact force per unit area. THIS is what allows penetration... Have a bone splitting day

BTW, the data above is specific for a bow that shoots a 350gr arrow at 315fps. You're results will vary from the data above if your bow shoots a 350gr arrow at a different velocity. If you're fairly close +/- 10fps, there won't be much difference in your results.

The PSE Nova is not as powerful as the Mathews FX. This explains the 200mm penetration difference. I really believe that the Nova is plenty powerful enough for taking a Kudu. My only suggestion is to use a strong, two blade broadhead such as these listed below:

1. G5-B52 http://www.g5outdoors.com/Products/ProductDetail.aspx?productid=1

2. Silver Flame http://www.german-kinetics.com/html/english.html

-Or- other heads with similar construction. Have a great hunt!!

The bow should work very well. PSE in the last few years had to improve their bow speeds to stay competitive. The older ones were slow but still killed very well, just had a poor trajectory. The old bows were very stabile and accurate. It takes the companies more work and design to gain back stability with speed. Maybe why they cost so darn much today. Then they have to bust their humps to get them quiet.
I picked up one of my Brownings for $89 on a year end close out. Now I see prices of bows to almost $1000. My Browning will shoot a 650 gr arrow 238 fps, I don't need any more! That gives me almost 82 ft pounds of energy and a very flat trajectory.
I watched a friend shoot a moose with his fast bow with 100 gr mechanical heads. He hit the leg bone and the arrow bounced out. There was 3" of blood on the shaft. My arrow would have cut off the leg.

Mechanical heads should be relegated to the "toy" section of the archery department... They suck!!!

Watch the arrow flight out of both bows.

If the PSE is not tuned to perfect flight then you will see the arrow corkscrew a bit in flight. This will usually cause the broadhead to plane also.

Anything other than perfect arrow flight will kill penetration.

You can check arrow flight by shooting through paper at varying distances. The arrows should make "bullet holes" with the fletching tears centered on the tip tear.

Another evidence of improper arrow flight is the arrows sticking out of the target at an angle off from the line of flight.

Don, you're right, but we have to base everything on the premise that the bows are in tune. But then, we don't know how many guys can tune a bow. A lot go to an archery shop and have someone else do it. And that just doesn't work because everyone doesn't shoot the same.

quote:

Originally posted by ghundwan:


How do you check if your penetration is sufficient for Wildebeest / Kudu sized game?

Thank you

(click pics to enlarge)



70# recurve 595 gr.arrow(202 fps)...very dead wildebeast. One arrow top of heart.



Same set-up, better heart shot!

Some might say I didn't have proper K.E. to hunt these animals. Fortunately, these two weren't very good at arithmetic.

BTW - Both were pass-through shots.

Boss, we both know K.E. doesn't mean a thing unless there is weight behind it. You were set up very well. Velocity means nothing without weight. A good arrow around 200 fps is very lethal.

quote:

Originally posted by bfrshooter:
Boss, we both know K.E. doesn't mean a thing unless there is weight behind it. You were set up very well. Velocity means nothing without weight. A good arrow around 200 fps is very lethal.

Thank you, my friend.

All the therorys & formulas are wonderfull to talk about. But, it still gets down to waiting for the right shot oppertunity and putting the arrow on the in the vitals.

I let BOTH of those animals come into around 15 yrds. Just like thousands of ethical bowhunters do season after season.

quote:

Mechanical heads should be relegated to the "toy" section of the archery department... They suck!!!

True for most of them but, not for all of them. If you will take a look at the broadhead test site, you will see that some of the mechanicals fair very well. I shoot a couple of brands that did well in those test and they do very well on animals such as deer. You can shoot them into a target next to a fixed and they penetrate much the same. As long as they have good sharp blades, sturdy construction, sound design, and shoot through a deer quartering and bury into the ground, they are all I could ask for from my set-up.

I've had full penetration through the center of the back bone on a whitetail w/ the NAP ShockWaves. To top that off, I took the same arrow w/ the same head and shot a doe a few days later, it went through the deer and buried deep into the ground where it hit a root. That first dropped, the second went approx 15 yards before expiring.


Some of the expandables are terrible but, not all. Just the same w/ fixed heads.

Reloader

Reloader, they have improved them. I would only use one with a cut on entry tip unless the bow is very strong. Then I would want one that will not break. I have found no need for them with my bows that tune very easy for any head. I like the Snuffer, Thunderhead and some of the Cabela's heads.
When they first came out, they were only a crutch for poor tuning. I remember the first ones that would break or lose blades in the chest of a deer. I even have some of Hal Rothgery's scissorheads in my collection. They either cut a 4" slot through a deer or failed completely.
Then there were the original fixed blade heads that were supposed to be aerodynamic, designed for recurves that are hard to tune. Real pieces of work! The worst were the original Wasp, Hilbre and Rocket head. Hit a bone and they just broke.
With compounds being so easy to tune, I can even shoot the original windplaner, the Pearson Deadhead! You guys would really love that one.

I agree, They have improved them in the last few years. I originally used them in a bow that was very diffcult to tune properly, seems like some bows are just plain stubborn. Those heads didn't penetrate very well.

I think another thing some folks don't realize is the lack of penetration they get w/ their expandables has some thing to do w/ the huge cutting diameter some exps have quite a large CD once opened. The good heads w/ 1-1/4" to 1-3/8" CD do quite well.

On the speed and tuning issue, I've looked at these new short fixed blade heads that a few manus have brought out. The concept seems like it would work since they do offer less area to affect the flight but, they have awful small cutting diameters.

Reloader

I used one of those little Ironheads on a deer , just once, Double lung hit and the deer went forever. Very small blood trail and very small hole in the deer. I will use them for woodchucks and rabbits.

I have done exstensive testing, in the field on game, with broadheads. Penetration has so much to do with broadhead style. Cut on contact will ALWAYS penetrate more than chisel tips and mechanicals. Does this mean they kill better? No, but what I found with the cut on contact was you can take severly quarting animals, confidentley and consistently, without worry of wounding. I used the same bow, arrows and media(hogs and deer) with different broadheads and found penetration to vary drastically. I tested NAP Spitfires and Thunderheads, Muzzy 3 blade chisel tips, Montec G5, Magnus (3) blade and Zwickey/Magnus (2) bades. All around best killer, flier and penetrater was the Montec G5. When you had a dead broadside shot the Spitfires cut huge wound channels and left unreal blood trails but never passed through. I use the G5 with great confidence and would shot anything with it. I shot a monster hog that was coming up a trail straight at me. At 15 yards he pulled up knowing something was not right. I saw him coming and was already at full draw when he broke out of the grass across from me. Looking straight at me I let one go and hit him just below his nose. He wheeled around and ran back the direction he came with my arrow sticking 2 feet out of his rearend. He went 15 yards and dropped dead. That was actually my first experince with that broadhead and was really impressed. Anyway, long story longer, try Montec G5 and you wont be anything but pleased.

Perry

Perry,

If you ever want to give the Mechanicals a try again, give the NAP Shockwaves a whirl. They penetrate much better than a spitfire. The spitfires are notorious for not penetrating on some shots.

Have a Good One

Reloader

The G5s shoot like little darts. I cant see a reason to shoot mechanicals. I am not oppossed to them, I just like knowing I can shoot through anything at any angle with lethality. The Shockwaves look awesome. I had a buddy who shot a zebra that was quartering away from him and he took out half the ribcage before hitting the vitals. Pretty impressive for a mechanical.

Perry

Arrow speed and weight KE(arrow weightxarrow weight x speed / 450240) are one of the factors ...Assuming both PSE and Mathews shot at the same velocity and used the identical arrow shaft and broadhead then they should penetrate pretty much the same distance in a consistent target. So the brand makes no difference in penetration ..just that one design may be superior and allow you to shoot more accurately, have less hand shock etc etc. I would think a properly tuned compound/recurve 62lb bow with cut on impact broadheads would shoot clean thru any Kudu that ever lived.

We have just bought 125gr thunderhead broadheads (3 blade)

Our biggest fear is poor penetration, will these do?

If you stay clear of major bones, the Thunderheads should do just fine. I wouldn't count on pass thru's, but I wouldn't be surprised either. Just practice, practice, practice, and when the moment comes, you'll know exactly how and where to deliver the arrow. If you do that, you'll be having Kudu chops for dinner

ghundwan,

You probably already know this but, be sure your bow and arrows are tuned well w/ the Thunderhead broadheads (or any other fixed blade head). Many fixed blade heads do not fly like field tips. I have had good luck w/ the Thunderhead 125s flying true when bow and arrow both were well tuned. I keep 6 of them in my box w/ new blades for my go to heads. That said, don't expect to use nothing but field tips while practicing and then expect the broadheads to have the same impact point.

Good Luck

Reloader

ghundwan, I shot my first elk a big fat cow clean thru the lungs at 30 yards shooting a finger released Thunderhead 125 and a 2315 shaft out of a 70 lb Oregon bow. The Oregon bow while very reliable and quiet did not have the arrow speed any modern bow today possess. I took great pains to make sure the bow was tuned properly. The thunderheads are great broadheads.

quote:

Originally posted by ghundwan:
We have just bought 125gr thunderhead broadheads (3 blade)

Our biggest fear is poor penetration, will these do?

American bowhunters tend to be very loyal and opinonated about about our broadheads. Many Trad shooters and African PH's prefer 2 blade heads.

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Our reasons are simple and proven. No moving parts to fail or fall off, two blades "tend" to "slide" past bones. It is very difficult to get 3 blade heads between ribs CONSISTALY w/o cutting ribs. When any head starts cutting bone upon penitation they lose energy...engery that is needed to continue through the animal.

Well made 2 blades are very strong. I used steeforce broadheads in Africa. I wish I wouls have save the rib my arrow hit on the exit side....I cut a 2" x 1/2" chunk of bone off the rib and still passed through.

These are my thoughts, and nothing negitive ment about others broadhead choices.

Best of luck with your hunting.

Were do you hunt?

Boss...is right. For penetration and no chance of anything malfunctioning 2 blades are the way to go. The blood trails are not as good but a lot of the times they pass through so fast game is not spooked and does not run as far. I shot a buck with a Zwickey 2 blade that ran about 20 yards and then started fighting a tree. 30 seconds later it just reared up and fell over dead, never knew it had been hit.

If I remember I think Howard Hill stated the ideal broadhead is a two blade with the length 3 times the width.
More like running a sword through the animal instead of a wood chisel.

Thanks for all the advice it has set our minds at ease, the rest is now up to us !!

Boss

We will be hunting at the end of this month in Tzaneen in the Northern Province SA. It is on a 2000ha game farm. I will post pictures when I come back, if I can figure out how.....

quote:

Boss

We will be hunting at the end of this month in Tzaneen in the Northern Province SA. It is on a 2000ha game farm. I will post pictures when I come back, if I can figure out how.....

Best of luck!!! The animals In my pics were from the Mesina Area.

When your back get the pics on your computor then go to this site to host your pics to post here.

http://www.imagevenue.com/

Thank-you all for all your advice. Unfortunately we went on the 4 day hunt and nothing came within 50m so we didn't shoot one arrow

We are going again second weekend in June to a different farm will post pics Hopefully !

That's why they call it hunting rather than shooting.

Better luck next time.